Improved roadway-pavements



@eine tetes stnt @fitta JOHN T. PARSON, OF WASHINGTON, DISTRICT OFCOLUMBIA.

Letters ,Patent No. 77,208, dated April 28, 1868; antedated April 18,1868.

IMPROVED ROADWAY-PAVEMENTS.

TO ALL WHOM I T MAY CONGERN:

Be it known that I, JOHN T. PAnsoN, of Washington, in the county ofWashington, and District of Columbia, have invented a new and usefulImprovement in Roadway-Pavements; and I do hereby declare the following4f to be a full, clear, and exact description of the same, referencebeing had to the accompanying drawings, in I WlllCh-r- Figure 1represents a perspective view of a section of a street paved with myimproved paving-blocks, Figure 2 a portion of street, having dierentforms of paving-blocks, and f Figure 3 a perspective view of a singleblock, such asis shown in iig. 1. It is well known that apaving-material suitable to withstand the heavy tralic of business incity streets, and at the same time' give perfect satisfaction is a greatdesideratum. Against every-material hitherto intro# duced, graveobjections have been made. Stone is either too rough, or wears (toosmooth, is too rigid, and is very costly. Iron is costly and too rigid,and wears too smooth. Wood is costly, and has not sullcient'durability.

Concrete or composition is also wanting in durability. The paving-blockwhich is herein described possesses the requisite qualities for agoodpavement to a greater degree than any material hitherto' in use, andis less liable to the defects above mentioned.

That others may fully understand my invention,v I` will particularlydescribe it.

The material which I employ is a refractory clay, such as is known tobrick-makers -as a strong clay, A

which is dicult to manipulate in tempering, and which, when made intobricks with the ordinary burning, is too hard and refractory for use.This clay, I have discovered to possess the requisite qualities to forma. goodpavement when properly tempered, pressed, and burned. It shouldbe thoroughly ground and mixed together, v without the use of muchwater, reducing it to the consistency of a still' putty. While in thiscondition, itis pressed into proper ferm by meansvof machinery ofsuitable power, and, after slight drying, the blocks so formed areplaced in a kiln and burned, a longer time and more intense heat beingemployed than inthe burn;

ing ot ordinary brick. When this process has been completed, the block-sready to be laid in the street.

These paving-blocks may be made in the form of a rectangle, circle, orpolygon, as may be deemed most desirable, and of such size as may bepreferred, but I thinl; the following. form and dimensions willbe foundmost advantageous, z'. e., the face or end to presentan octagonalfigure, with unequal sides of about two and one.-

fourth (2i) inches, and one (l) inch alternately, as shown in iig. 3,'the diameter being nearly four (4) inches. This surface forms the faceor exposed end of the paving-block, and it should be supported by adepth of about eight (8) inches, the whole represented in perspective iniig. 3. When forming a pavement o-f these blocks, the bed is prepared insome suitable manner, depending very much upon the natural subsoil ofthe locality. If the same is soft, a deeper and rmer foundation must belaid than if it is solid and firm naturally. When the bed is properlyprepared, the blocks are laid, as shown in iig. l, leaving aninterstice, a, of about one (1)*in-ch square between the blocks at eachcorner. When a considerable space has been laid with the blocks, asquare wooden pin of proper size may be driven into the interstices a Qand *thev blocks all keyed firmly. The spaces between the blocks maythen be filled with sand or cement, as in the ordinary manner of layingpavements.

The use of the wooden keys is not deemed essential', but useful,especially in pavements required to with; stand a heavy trahie. 1 y

The form and dimensions above mentioned secure the following advantages:The form of the exposed end permits the occurrenceof small holes oropenings in the pavement at intervals of about four (4) inches over theentire surface of the pavement. These holes pass through to thefoundation, and l'will' therefore be always present. They are ofsuchsmall size as to alford a convenient and sure holding-place for thecalks of the horses shoe, so that there can be no dangerous slipping'upon this pavement, however smooth the surface of the paving-v hlockmaybecome. The small diameter of four (4) inches, or thereabouts, bringsthe joints between the different courses so close that the surface ofthe pavement will never become perfectly lat and smooth, because theedges Will wear a little faster than the centres of the blocks, andthese inequalities will alone afford good footing for the horsesvtravelling over it. The octagonal form permits the blocks to be laid sothat their longest sides are diagonal to Vthe side of. the street, as`shown in iig. 1, and the wheelsof carriages will thus 'seldom passlength- Ways over any of" the joints, and will therefore tend Vlessl tobreak theedges down. The whole dimensions of the block will be sucientto 'give it the requisite strength and balance when laid to form a solid`and rm pavement. Thermaterial above mentioned, when prepared asdescribed, is har-der` and; stronger than granite or any other stonehitherto used for pavement, yet itis somewhat porous, and isthereforemore elastic and lghter'than stone. Its porosity enables it to absorbwater to a'slight degree', `Iand it will therefore require lesssprinkling to keep down the dust. It isy not at all friable,`and"itsabrasion will be slow, ami in v'ery minute particles, which will beeasily removed by washing or sweeping. l y

The small' and regularly-recurring holes a a maybesecured in other formsthan octagonal, (see iig. 2,) but it is evident that the octagonalis themost' advantageousffom'. l i

The wooden keys may be saturated with coal-tar, or submitted to anyother preservative process, if' desired, before being driven into place..When it is desirable tol-remove a'vporton of the pavement, to lay downpipo, dac., the Wooden keys maybe displaced b'y driving them into thesoil beneath. or otherwise, and then one or more ofthe paving-blocks maybe easily removed. p i i i i f Having described my invention, what Iclaim as new, s l

A paving-b1ock,ha.ving an octagonal-shaped end, composed oclay treatedas described, aml for the purpose yset forth. 1

A. paving block of octagonal or other form, designed and arranged so as,when laid, tovleave small holes' at regularly-recurring intervals, forthe purpose set'fortb. l Y 4 The herein-described baked or burn'edclaypaving-block, as a new article offmanufacture. 4

The combination, to form a roadwaypavem entfef paving-blocks, having anoctagonal or other form, designed and arranged so as, when laid, toleave small holes at regularly-recurring intervals, and wooden keys",substan.

tially as described. I u Y JOHN T PARSON "ywitnessesz D. B. VENTRE,

E. J. BROWN.

